Although many people take much higher doses of vitamin C, it's not clear that high doses have any benefit. Some studies have found that doses above 200 milligrams are not utilized by the body. Instead, the extra vitamin C is excreted in urine.

The tolerable upper intake levels of a supplement are the highest amount that most people can take safely. Higher doses might be used to treat vitamin C deficiencies. But don't take more unless a doctor says so.

Category (Children & Adults)

Tolerable Upper Intake Levels (UL) of Vitamin C

1-3 years

400 mg/day

4-8 years

650 mg/day

9-13 years

1,200 mg/day

14-18 years

1,800 mg/day

19 years and up

2,000 mg/day

Can you get vitamin C naturally from foods?

Many people get enough vitamin C from their diets. All fruits and vegetables have some vitamin C. Some of the best sources are:

Green peppers

Citrus fruits and juices

Strawberries

Tomatoes

Broccoli

Sweet potatoes

Light and heat can reduce vitamin C levels. Fresh and uncooked fruits and vegetables have the most vitamin C.

Interactions. If you take any other regular medicines, ask your doctor if it's safe to take vitamin C. It can interact with drugs like aspirin, acetaminophen, antacids, and blood thinners. Nicotine may reduce the effects of vitamin C.

Risks. People who are pregnant or have gout, liver disease, kidney disease, and other chronic diseases should check with a doctor before using high doses of vitamin C supplements.